【单选题】

Water displacing corrosion inhibiting compound has been applied during construction on certain airplanes in the locations shown in this figurE. Periodic reapplication in these, and other locations, is required to maintain effectiveness of this protection.

A、At the location shown in the figure, waterproof corrosion inhibiting compound has been used on certain aircraft construction. To keep the effectiveness of this protection, reapply the compound in these and other locations periodically.
B、Water displaying corrosion inhibiting compound has applied on certain airplanes structure in the locations in this figurE. Periodic reapplication must be applied in these and other locations, so as to maintain effectiveness of this protection.
C、Water displacing anti-seize compound has been applied on certain airplanes construction in the locations in this figurE. Periodic reapplication should be utilized in these and other locations, in order to keep effectiveness of the protection.